Hello and Welcome to a simple beginners electronic project. Today I am going to show you how to make a transistor tester that is used to determine whether a transistor is NPN or a PNP. If its a NPN then the circuit should light up. This also an easy way to tell if your NPN transistors are working and will save you tons of time in the long run.

NPN transistors use the format of EBC which stands for Emitter Base Collector.
PNP transistors use the format of ECB which stands for Emitter Collector Base.

Step 1: Materials

Well I had most of these materials on had so this project did not cost me a dime but if your lucky like me I'm sure you could get everything for under $5 if you scavenge for old components. Everything here is cheap and should be found locally in old electronics except for the 9 volt battery which I happen to have a case of. However the case was made out of bendable plastic sheets that I got from my art class if your creative you can make the case out of anything.

Stuff Needed:

LED of any color
9 volt battery
bendable material to make the case
3-4 pin socket for transistor
10k ohm resistor
470 ohm resistor
NPN transistors
Small Switch

Step 2: Testing

Before any electronic project goes to soldering or finalization you should always check with a breadboard that everything is working and that all the components are fine. This 5min check could save you from frustration later on after spending show much time soldering it to together to find out that your contraption doesn't even work.

Step 3: Construction

Now we will start of by soldering the components together just follow the circuit that has been attach and you will continue on until your done. You can choose to do it on a circuit board but for simplicity sake I just did it with out a circuit board and positions the joints in a way that wont allow for short circuits win place in their casing.

The transistor circuit I found was used as a way to learn transistors I just modified the circuit by allowing the transistor to be removable therefore leading to the circuit now becoming a transistor tester.

Step 4: Casing

I made the case by first printing out the scaled up template I designed for a portable use. I printed out the sheet and then laid it below the plastic material. I basically traced out the case with an knife, and then glued it back up together with hot melt.

Indesign file: http://www.mediafire.com/?zznuwjqnz2k1dqi Use this link if you want to edit the measurements.

Exact Scale File: http://www.mediafire.com/?ih942ca3h8jmd5i

Okay at this point I hot melt the circuit components in to pre-cut openings and I was constantly checking the connections to make sure everything was in order by having the transistor in the place lighting up the LED the whole the time. You would hate for a fault in the wiring after you closed everything back up with hot melt.

Step 5: YAY Finish

Okay that's it and everything should be in order now. This is first in a series of instructables that are soon to come.
Thank you for your time and if you have any comments feel free to tell me.